#include<iostream>
#include<iomanip>
#include<string>
#include<vector>
using namespace std;
class SalesItem
{
public:
	SalesItem():isbn()
	{
	}
	SalesItem(string s):isbn(s)
	{
	}
	bool SameIsbn(const SalesItem s)
	{
		if(s.isbn==this->isbn)return true;
		else return false;
	}
	friend istream& operator>>(istream &in,SalesItem &s)
	{
		in>>s.isbn>>s.units>>s.price;
		return in;
	}
	friend ostream& operator<<(ostream &out,const SalesItem &s)
	{
		out<<s.isbn<<" "<<s.units<<" "<<s.price;
		return out;
	}
	SalesItem& operator+(const SalesItem &s)
	{
		SalesItem r;
		if(s.isbn==this->isbn)
		{
			r.isbn=this->isbn;
			r.units=this->units+s.units;
			r.price=this->price;
		}
		return r;
	}
private:
	string isbn;
	int units;
	double price;
};

char* ptr()
{
	char p[]="Hellow World!";
	return p;
}
int main()
{
	vector<int> a;
	a.push_back(2);
	a.push_back(3);
	cout<<a.max_size()<<endl;
	cout<<a.capacity()<<endl;
	cout<<a.size()<<endl;
	/*SalesItem book;
	cin>>book;
	cout<<book<<endl;*/
	return 0;
}